Methane is a colorless, odorless, flammable gas. The relative density is 0.5547, the boiling point is -164°C, and the melting point is -182.48°C. Methane is an important fuel and an important chemical raw material. Natural gas with methane as the main component is a high-quality gas fuel with a long history. It has been exploited and utilized on a large scale and has become the third energy source in the world.